Certain devices, such as payment card chips and SIM (subscriber identity module) cards, are likely to store or process sensitive data that should be kept secret. Examples of sensitive data include encryption keys or other data processed during a cryptographic operation. A fraudster attempting to access the sensitive data may use a laser, generally applied to the back side of the integrated circuit, to introduce electrical disturbances in the circuit during its operation, which then allows information regarding the sensitive data to be discovered.
It has been proposed to provide detection devices for detecting the presence of such laser attacks. When an attack is detected by such a detection device, a counter measure can be triggered, which may for example involve resetting the device and/or the destruction of the sensitive data. The device may even be permanently disabled if for example a certain number of attacks are detected within a relatively short time interval.
A drawback of existing detection devices for detecting laser attacks is that they tend to be ineffective for certain types of laser attacks, and/or occupy a relatively large chip area.